Improvement in gbinding-ptates fob gbist-mills



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HENRY SHAW AND WILLIAM n. IiEAvITT, ou NEW ORLEANS, LOUISIANA.`

' Later@ Paraninfo. *rasca-dated .my 14,1s6s.

IMPROVEMENT IN GRINDING-PLATES FOR GRlST-MILLS.

'IO ALL WHOM IT MAY CONGERN:

Be it known'that we, Humm SIIAW and WILLIAM D. Lsiivrrr, of thc city of'New Orleans, parish of Orleans, and State of Louisiana, have invented a'ccrtain neu' and useful Improvement in Cast-'Iron Grindingv -Platcs fouGrist-Mills; and we do hereby declare the following 'to be a. ful1, clear, and exact. description of the same, reference being had to the 'annexed drawing,`making a part of this'specification,` on which isi-'delineated a. perspective view of one of the grinding-plates of a eastiron Agristnill,y with a part broken away in order the more clearly to exhibit the most important features of our invention. Our invention has foritsobjeet the prevention of the injurious Aand often destructive cfect'scaused to'thc meal by the hea-t generated in all mills through the friction oi` theIIjubbing-surfacesof the two'` opposing plates during the operation of grinding; and We attain this object by constructing each of the two grimling-plates in two parts,'viz, a grinding-face plate, anda back or supportingplate,'with an intermediate part or packing of unyielding and non-conducting properties, so that the two grinding-faces will consist of thin plates, andsothat such heat as is generated bythe friction caused in grinding, being prevented fromcommunicating to the remaining part ofthe plate,- or any other part of the milLor, in other words, b eing confined to the thin grindingface, will pass olfewith the meal as yfestas the latter is ground, and bcforea suicient quantity of heut is gene# rated or accumulated to injure themeal. i

Another feature of our invention, having in view the furtherance ofthe same object, is the peculiar dress of-tho grinding-faces of our plates, which consists of a system of diamond-shaped projections, tvhich radiate-.in rows or' lincsfrom the centre ofthe. face-plate, `and are so arranged, that in the revolution of the runningplate against the stationary one,- a multitude of cutting-edges is created, which come together after the manner of the blades of a pair of shears, nnd'so eut the grain, instead of crushing or breaking it, as is -the casein'most mills. It will readily be seen. that this shearing or cutting process reduces, to a-certain extent, the tendency to overheating, by reducing the friction of the plate against the grain.

B ut our` inventionwill be better understood by referring to the'drawing, on which A represents the diamond-Y shaped-dress-.nponthe thin grinding-facq, of the plate. C is the non-conducting, unyielding intermediate packing, which may be composedof gasket, paper, or any other substance havngu-nyielding and'nonfconducting properties. D is the back part or supporting section ofthe grinding-plate,torihch the face-plate B is secured by Strong screw-bolts (shovfn at E in -tl1e drawing) passing throughand confining in its position the intermediate packing C, the whole forming, when screwed u p, a strong' and compact grinding-plate'.

`The drawing. showscnly one of the grinding-plates, but it will be understood thatiin eachmill there is another plate preeiselysimilar to the one shown in; the drawing to its "dre s srand sectional or divisional construction. v A

Having thus described our invention, we claim,land desire to secure by Letters Patent- The combination andarrangement ofthe' cast-irongrinding-plate B, having diamond-shaped projections the unyielding, non-conducting paper packing C, and beck. plate D, all constructed and secured together in the manner and for the purpose herein described.

` HENRY SHAW,-

W. YD; IiliAVIWl.-V

Witnesses H. S. BLooD, H. N. JiannINs, 

